Invertible timers



Feb. 28, 1967 J. L. LILJEQUIST 3,306,029

INVERTIBLE TIMERS Filed Aug. 6. 1965 ia- 41M United States Patent Ofiice 3,306,029 Patented Feb. 28, 1967 3,306,029 INVERTIBLE TIMERS Jon L.Liljequist, 507 W. Algonquin Road, Arlington Heights, Ill. 60005' FiledAug. 6, 1965, Ser. No. 477,828 7 Claims. (Cl. 58144) This inventionrelates to timers, and more particularly to a mechanical timer utilizinga shift in its center of gravity to cause a pivoting of the timer andindicate lapse of time.

Limited duration timers of the type utilizing the movement of a massunder the influence of gravity are one of the oldest forms of clocksknown to man. An example of this type of timer is the ordinaryhourglass, currently in wide use for the timing of soft-boiled eggs andtelephone calls. Although these timers are popular because they aresimple and inexpensive, they have the inherent disadvantage of requiringthe user thereof to pay close attention to the movement of the sanddownwardly in order-to be aware of completion of the timing function.Where the user is involved in doing other things during his timingoperation, it frequently happens that the timer completes its timingoperation outside of the view of its user. For example, this might occurwhen a person is using the device to time the cooking of eggs, and atthe sam;: time is attempting to prepare other portions of the mea Itwould, therefore, be desirable to have atimer of this simple andwell-known variety which is capable of giving the user a more readilynoticeable indication of the lapse of time, this indication notrequiring strict visual attention to the timer at all times.

Although a timer of the hourglass variety normally increases instability because of the downward movement of the sand and consequentdownward shift of its center of gravity, it will be seen that in thetimer to be described that the timer becomes less stable as the centerof gravity moves downwardly until the timer reaches a point of totalinstability and tips over. Thus, the timer not only gives an easilynoticed indication of the passage of time, but also stimulates curiosityby appearing to defy the laws of nature.

It is, therefore, a general object of this invention to provide a newand improved limited duration timer which pivots over a limited arc toindicate the passage of some predetermined length of time.

It is an advantage and a feature of the present invention to provide alimited duration timer which becomes in stable in its placed positionafter passage of a given amount of time so as to give a definite andobvious warning of the passage of some fixed amount of time.

Another advantage and feature of the invention is the provision of asimple gravity-operated timer utilizing the downward movement of agravity-biased mass therein for the measurement of time, said timerbecoming instable and tilting to a more vertical position both to givean indication of'the passage of some given period of time as well aspermitting the downwardly moving mass to complete its travel to itslowermost position.

Other objects and advantages will become apparent upon reading thefollowing description, to be taken in conjunction with the accompanyingdrawings in which:

FIG. 1 is a perspective view of one form of the timer incorporating thebroad principles of the invention;

FIG. 2 isa cross-sectional view of the timer shown in FIG. 1 takensubstantially along the lines 22 of FIG. 1;

FIG. 3 is a cross-section of the timer shown in FIG. 1 and is takensubstantially along the lines 33 of FIG. 2;

FIG. 4 is a view substantially the same as that shown in FIG. 3, but ina tilted position therefrom to assist in an understanding of the timersaction;

FIG. 5 is a perspective view of a slight variation of the inventionshown in FIGS. 1-4; and FIG. 6 is a side view of another variation ofthe invention.

While several illustrative variations of one general form of theinvention are shown in the drawings and will be described in detailhereafter, the description and drawings are to be taken merely asillustrative of the principles disclosed therein and are not intended tolimit the invention to the variations shown and described, nor are thesevariations intended to define the scope of the invention. The scope ofthe invention will be pointed out in the appended claims.

Referring now to the drawings in detail, FIGS. l-4 show one variation ofthe preferred from of the invention. The timer shown generally at 10includes a main body 11 which contains an internal and entirely enclosedhollow or void 12 Internal void 12 includes upper and lower chambers 13and 15, and carries therein a movable mass 16. Mass 16 may consistof anysuitable material, such as a liquid or solid, and in this variation isshown as a finely-divided material, such as sand. It will be understoodthat the intemal configuration of this variation of the timer operatesin the same general manner as a conventional hourglass, the enclosedmass 16 being permitted to move between upper and lower chambers 13 and15 under the influence of gravity when the timer 10 is properlypositioned on a surface such as 17.

Means are provided for retarding or metering the downward movement ofmass 16, and in this variation these means consist of a restricted area18 which both separates and joins chambers 13 and 15. It will beunderstood, as in ordinary hourglass design, that the size ofrestriction 18, in conjunction with the type and quantity of sand used,are the principle factors which determine the amount of time it requiresfor the sand to move entirely from the upper hollow or chamber 13 to thelower chamber 15.

Although the above-described timing operation corresponds with theoperation of an ordinary hourglass, means are herein provided for givinga user of the time a more readily noticeable indication of the passageof time than ordinary hourglasses permit. Although these means are shownas an integral part of main body 11, it will be understood that theycould easily be attached to existing hourglass designs to perform thesame function. These means consist of upper and lower compositesupporting means 20. These supporting means 20 include a limitedstability surface 21 which intersects a second supporting surface 22 atan obtuse angle, thus forming a common edge 23 about which the timer canpivot. Composite supporting walls 20 are joined by a plurality of sidewalls 25, 26, 27 and 28 which define internal void 12 and which areinclined at a sufficient angle to ensure that the sand can flowtherealong under the influence of gravity when the timer is placedeither on supporting surface 21 or 22. As can be seen in FIGS. 2, 3 and4, the slope of all of these walls exceeds about 45 degrees when thetimer rests on either of surfaces 21 or 22 to ensure that the sand willflow in either position of the timer. Furthermore, side walls 27 and 28are shaped so as to cause the center of gravity of the sand to movelaterally as well as downwardly as it flows through restricted area 18into the lower chamber. The operation of the timer makes use of theinteraction between the composite supporting means and the lateral shiftof the center of gravity of the sand, and will be described next.

Referring now to FIG. 3, the center of gravity of the sand, immediatelyafter inversion of the timer, is generally in the area designated 30.The center of gravity of the main body is, and remains, at the place ofthe restricted area 18. Assuming that the walls of the main body 11 arekept as thin as possible, to minimize the weight of the main body, thecomposite center of gravity for both the sand and the main-body would begenerallyatthe position "designated as 31. zlnasrnuch" as this compositecenter of 33. At this instant, the composite center of gravity isdirectly over pivotal edge 23. It will be understood that further sandflow shifts the composite center of gravity to the left of 33 in FIG. 3which is beyond the last point of support that surface 21 can provide,thereby rendering the timer unstable and causing it to pivot into theposition shown in FIG. 4. After tipping onto surface 22, the sides 27and 28 permit the last remnants of sand to flow downwardly into thelower chamber. This movement, along with any accompanying noise such asthe slap of surface 22 onto horizontal surface 17, gives an indicationto the user ofthe lapse of some predetermined quantity of time asdetermined by the design of the specific timer used.

It will be noted that the upper half of one of the walls 27 and 28 isvertical and the other a fixed angle therefrom when the timer is placedon either of its two lower supporting surfaces, thereby ensuring thatthe rate of sand flow is identical regardless of which surface supportsthe timer. Also, the timer can be designed to tip at the end of a givenperiod or at some short interval before the end of a given period as awarning. As an example of this latter design, a three-minute egg timercould be designed to tip at the end of two minutes and forty-fiveseconds, after which the remaining sand would take 15 seconds to vacatethe upper chamber and complete the three-minute timing cycle. If it isdesirabe in a given application to have a more audible indication oftime lapse than that resulting from the timer tipping onto surface 22, asimple impact bell could be attached to the side of the timer.

Preferably the entire main body is molded or cast of a light-conductingmaterial, such as glass or plastic, and is kept at a minimum weightrelative to the sand so as to get maximum sensitivity. When the wallsare made very thin, additional structural support may be added in theform of webs 35.

FIG. shows a slight variation of the timer and includes anhourglass-shaped void 40 formed as an integral part of an otherwisesolid block 41 of clear material. This design gives a pleasingappearance to the timer making it suitable for use in an office as acombination phone call timer and paperweight. Block 41 includes a numberof beveled edges as at 42 and 43, on which it can be supported duringthe timing operation. It will be understood that edges 42 and 43 performthe same function as supporting surface 21 performed in the previouslydescribed variation. However, edges 42 and 43 can be made slightlydifferent in size and shape from one another so as to cause the timer totip after the lapse of different amounts of time, depending on which ofthese two surfaces the block 41 is supported. For example, when invertedand supported on edge 42, the timer could be designed to tip up at theend of two minutes, whereas if it were supported on edge 43, it might beso designed as to tip up at the end of two and one-half minutes.

FIG. 6 shows a further variation of the timer wherein the main body 50is pivotally supported about a pin 51 attached thereto. Pin 51 rests inthe cradle portion 52 of a pair of supporting legs 53 which are rigidlyaffixed at their lower portions to a supporting base 55, said base beingadapted to rest on any suitable surface such as the one shown at 56..Main body 50 includes an internal and elongate void 57 of cylindricalshape in which is movably carried a solid spherical mass 58, although,the same action would be obtainable if mass 58 comprised a generally 7spherical void, to be described in detail later. Means are j providedfor retarding or impeding the free movement of mass 58 downwardly, andherein these means comprise a fluid 60 entrapped in the void 57 whichentirely fills remaining portions of the void 57. The rate of movementdownwardly of mass 58 under the influence of gravity can becontrolled-in the design of the timer by proper sizing of the respectivediameter of the mass and cylindrical void as well as by a properselection of the fluid used, the material of'which the mass consists,and the length of the cylindrical void.

In operation, the main body is inverted and the upper pin 51 is placedin cradle 52 which supports the main body at an angle. shift in thetimers center of gravity causes the elongate dimension of the main bodyto slowly pivot toward the vertical. The same external effect can beachieved if the mass 58 is a large bubble or thin-walled hollow sphereof lesser specific gravity than the fluid used. In this case, the massmoves upwardly due to the buoyancy of the fluid to perform the timingfunction.

Although the variations of the invention shown and described eachpossess some'individual advantages, it'will be understood that certainof these are interchangeable among these variations. Furthermore, theteachings contained herein are not intended to limit the scope of theinvention to the specific means used to illustrate its principles. Othermeans of support are contemplated as well as other means to cause ashift in the timers center of gravity.

I claim:

1. A timer, comprising; a main body having an enclosed and elongateinternal void defined at each end thereof by a pair of spaced apart wallareas; mass means having a center of gravity movably contained in saidvoid for movement betweeen said spacd apart wall areas under theinfluence of gravity; means between said end wall areas for retardingthe free movement of said mass means between said spaced apart wallareas, thereby providing a metered movement of said mass means; andlimited stability support means for supporting the lowermost portions ofsaid main body in a stable position both with said elongate internalvoid tilted at an angle from the vertical and with said center ofgravity located above and to the side of its lowermost position, saidsupport means being of limited dimensions in the horizontal direction ofmovement of said mass means so as to lose its stable support of thetimer as said center of gravity approaches its lowermost positionthereby causing said timer to tilt and thus indicate the passage of somepredetermined period of time.

2. A timer, comprising: a main body structure having an internal andenclosed void of generally hourglass shape including upper and lowerchambers separated by a centrally located restricted area; and amoveable mass of finely divided material in said void and moveable fromsaid upper chamber to said lower chamber under the bias of gravity; saidmain body structure having composite supporting means including alimited stability supporting surface for supporting said main body withsaid upper chamber above and to the side of the lower chamber, saidcomposite supporting means also including a second supporting surfacewhich intersects said limited stability supporting surface at an obtuseangle, the intersection of said surfaces forming an axis about whichsaid timer can pivot, said axis being horizontally located between thehorizontal limits of movement of the center of gravity of said timerwhen said timer is supported on said limited stability supportingsurface so as to cause said timer to become unstable after a portion ofsaid mass moves from said upper chamber to said lower chamber, therebycausing said timer to tilt and indicate the passage of somepredetermined amount of time.

As the mass moves downwardly, the.

3. A timer comprising; a main body having an enclosed v and,elongate'finternal void defined at each end thereof by a pair of spacedapart wall areas; mass means having a center of gravity movablycontained in said void for movment between said spaced apart Wall areasunder the influence of gravity; means between said end wall areas forretarding the free movement of said mass means between the said spacedapart wall areas; thereby providing a metered movement of said massmeans; and limited stability support means for supporting the lowermostportions of said main body in a stable position both with said elongateinternal void tilted at an angle from the vertical to permit downwardand horizontal movement of said mass means and when said center ofgravity is located above and to the side of its lowermost position, saidsupport means being an integral part of said main body and defining aplane of support for resting said timer on a horizontal surface, saidplane of support being of limited dimensions in the horizontal directionof movement of said mass means so as to lose its stable support of thetimer as said center of gravity approaches its lowermost position,thereby causing said timer to tilt and thus indicate the passage of somepredetermined period of time.

4.A timer, comprising: a main body having an enclosed and elongateinternal void defined at each thereof by a pair of spaced apart wallareas; mass means having a center of gravity movably contained in saidvoid for movement between said spaced apart wall areas under theinfluence of gravity; means betweeen said end wall areas for retardingthe free movement of said mass means between said spaced apart wallareas, thereby providing a metered movement of said mass means; andlimited stability-support means for supporting said main body in astable position both with said elongate internal void tilted at an anglefrom the vertical to permit downward and horizontal of said mass meansand when said center of gravity is located above and to the side of itslowermost position, said support means comprising a first supportingplane for resting said timer on a horizontal surface, said support meansbeing of limited dimensions in the horizontal direction of movement ofsaid mass means so as to lose its stable support of the timer as saidcenter of gravity approaches its lowermost position, thereby causingsaid timer to tilt and thus indicate the passage of some predeterminedperiod of time; and other support means in the form of a secondsupporting plane onto which said timer tilts after passage of saidpredetermined amount of time, said plane being oriented to support saidtimer in a position with said elongate internal void being generallyvertically oriented to permit said mass means 1 to complete its movementto its lowermost position in said void.

5. In a limited duration timer incorporating a laterally movable masswhich is carried thereby to effect a change in the location of thetimers composite center of gravity, and wherein said change in locationrenders the timer unstable so as to cause the timer to move and therebyindicate the lapse of some predetermined period of time, the improvementcomprising: an integral supporting structure for said mass, saidsupporting structure including an upper end and a lower end rigidlyforming a part thereof, means between said upper end and said lower endfor A restricting the movement of the mass in an elongated pathgenerally therebetween, and limited stability supporting means rigidlyforming a part of said lower end and movable therewith for supportingsaid timer in a stable condition on a generally horizontal surface withsaid path having a horizontal component and for relinquishing saidstable support after a predetermined lateral movement of said compositecenter of gravity.

6. The improvement as set forth in claim 5, wherein said integralsupporting structure includes second limited stability supporting meansrigidly forming a part of its upper end and of a configuration simillarto the first men tioned limited stability supporting means for providinglimited support for said timer upon an inversion thereof to therebypermit a timing function when supported thereon.

7. The improvement as set forth in claim 5, wherein said limitedstability supporting means defines a lower plane of support on whichsaid timer rests, said lower plane of support covering a limited areadirectly underlying said composite center of gravity over only thefirstportion of its change in location whereupon a predetermined lateraldisplacement of said movable mass causes said composite center ofgravity to move laterally beyond said limited area and thus render thetimer unstable.

References Cited by the Examiner UNITED STATES PATENTS 199,419 1/18'78De Macedo 58-144 FOREIGN PATENTS 506,336 9/1930 Germany.

RICHARD B. WILKINSON, Primary Examiner. G. F. BAKER, Assistant Examiner.

1. A TIMER, COMPRISING; A MAIN BODY HAVING AN ENCLOSED AND ELONGATEINTERNAL VOID DEFINED AT EACH ENC THEREOF BY A PAIR OF SPACED APART WALLAREAS; MASS MEANS HAVING A CENTER OF GRAVITY MOVABLY CONTAINED IN SAIDVOID FOR MOVEMENT BETWEEN SAID SPACED APART WALL AREAS UNDER THEINFLUENCE OF GRAVITY; MEANS BETWEEN SAID END WALL AREAS FOR RETARDINGTHE FREE MOVEMENT OF SAID MASS MEANS BETWEEN SAID SPACED APART WALLAREAS, THEREBY PROVIDING A METERED MOVEMENT OF SAID MASS MEANS; ANDLIMITED STABILITY SUPPORT MEANS FOR SUPPORTING THE LOWERMOST PORTIONS OFSAID MAIN BODY IN A STABLE POSITION BOTH WITH SAID ELONGATED INTERNALVOID TILTED AT AN ANGLE FROM THE VERTICAL AND WITH SAID CENTER OFGRAVITY LOCATED ABOVE AND TO THE SIDE OF ITS LOWERMOST POSITION, SAIDSUPPORT MEANS BEING OF LIMITED DIMENSIONS IN THE HORIZONTAL DIRECTION OFMOVEMENT OF SAID MASS MEANS SO AS TO LOSE ITS STABLE SUPPORT OF THETIMER AS SAID CENTER OF GRAVITY APPROACHES ITS LOWERMOST POSITIONTHEREBY CAUSING SAID TIMER TO TILT AND THUS INDICATE THE PASSAGE OF SOMEPREDETERMINED PERIOD OF TIME.